Blower compressor unit for oil burners



Jan. 1,' Y1935.

w. o. U M

BLOWER COMPRESSOR UNI`T vFOR OIL BURNERS Filed July 25, 1931 2 Shee'bS---SheetI l 'W. Ov LUM Jan. 1, 1935.

BLOWER COMPRESSOR UNITFOR OIL BURNERS Filed July 25, 1951 2 Sheets-Sheerl 2 t 't WEQDO. (131m, 125 Maman., r His ,Aitor-17%.

Patented Jan. I, 1935 PATENT OFFICE 1,986,003 BLOWER COMPRESSOR UNIT Foa on.

Nens l BUR Walter 0. Lum, Schenectady, N. Y., assigner to General Electric Company, a corporation of New York Application July 25,1931, serial No. 553,119

30 Claims.

My invention relates to liquid fuel burners, more particularly to improvements in the oil and air pumps and blowermechanism normally employed in oil burners.

In oil burners heretofore used the oil and air pumps and blower mechanism are as a rule separate units and necessitate the use of considerable4 space at the oil) burner. Ordinarily no means are used for cleaning the air used for spraying the liquid fuel and very little effort is made to provide means for effectively cleaning the oil which is supplied to the oil burner. The use of separate units for supplying the air and oil under pressure to the nozzle results in pulsations at the nozzle which in turn cause roaring of the flame dueto the interaction of the pressure 4between the oil and air at the nozzle. As a rule no means -is provided for separating occluded air which causes an unstable flame from the oil. In theusual oil burner the pressure of the air delivered to theA nozzle varies with the speed of the air pump and no means is provided for maintaining the air pressure constant. The same is true of the pressure of the Oil delivered tothe nozzle.v All these features if not counteracted result in dilculties in the operation of the oil burner.

Hence it is a principal object of my invention to provide an improved self-contained oil burner unit comprising a blower, air compressor and oil pump which will overcome the diillculties Outlined above and in addition have these various elements in such cooperating and unied relation that they mutually increase the effectiveness and reliability of leach other in construction, installation and performance of their joint function of supplying clean oil and air underv stabilized pressures to' an oil furnace over long periods of time without appreciable noise, leaks, clogging, overheating or other troubles.

Another object of my invention is to provide Y an oil burner blower compressor unit which cleans unit of the above type in which the unit is self-r lubricating.

A still further object of my invention is to provide means for separating occluded air from oil j being delivered to the burner. e

'I'hese and other objects after,

will -appear herein- (Cl. 15S-36.5)

Briefly, the unit of my invention comprises a casing head forming a main chamber with a cover or casing in the form of a sump tank clamped thereto. On the top of the casing head and supporting a rotating blower fan is a motor mounted upon a vertical shaft extending through the casing and into the'sump. The motor used is an induction motor which is not subject to sparking. Mounted' on the lower end of this shaft within the casing is an air compressor and an oil pump which pump air and oil under pressure into the chamber and sump Where the oil and air are maintained by automatic valves under even, constant pressure. The air is cleaned of dust and dirt by making use of the motor and a pair of shields underneath said motor which cooperates of the compressor unit. A float valve regulates the oil level within the sump and a pressure valve regulates or limits the air pressure within the chamber. n second .discharge passage. The drilled shaft also provides for lubrication of the bearings of the motor shaft and a vapor relief chamber is provided at the oil discharge opening from the shaft or in the modification adjacent the end of the conduit for separating occluded air and vapor from. the oil.

In the drawings, Fig. 1 shows a cross-section of my blower compressor unit and Fig. 2 shows a section thereof taken4 on the line 2--2 of Fig. 1. Fig. 3 shows my invention applied to an oil burner boiler. Fig. 4 shows a cross-sectionv of a modification of my invention. I

Referring to the drawings, Fig. 1, the main chamber casing head 10 has clamped thereto by means of the segmental clamp 12 the cover' or casing 11 which forms the Oil sump tank. The segmental clamp 12 is made in sections andvconnected by means of links 14 and 15,- as shown in Fig. 2, which are held clamped to the casing by means of the screw 16. It will be noted that the clamp 12 is provided with a beaded rim 17 which engages. an annular sloping projection v18 r on the casing 10 andalso has an inturned bottom rim 19. The oil sump tank 11 is, provided with a rim 11 bent at an angle greater than 90 as shown in Fig. 1 and cooperating with the bottom rim 19. The purpose of this construction is The air leaves the unit by means of a such that any tendency of the tank 11 to move down from the casing 10 when under pressure forces the rim of the sump tank against the main chamber` casing 10, thereby causing a tighter' joint. AA gasket 13 is provided to supplement the t of the tank to the casing 10 and to insure a tight joint. The clamp permits the sump tank and the screen 59 to be removedv and cleaned when desired.

Vertically mounted upon the main chamber casing 10 is the electric motor 20 which is provided with a stator 21 and a rotor 22. The motor is of the induction type and hence not subject to sparking which would be extremely dangerous in such a unit. The rotor 22 has the axial air passages or openings 23 extending therethrough which open up into the chamber below the rotor to admit air thereto. The rotor is mounted upon the vertical motor shaft 26 which rotates in the Vbearing 27 and the bearing block' 27' at the botthe shaft. The rotor has attached tom end of thereto just below the rotor :a conical shield 24 which cooperates with the shield in a manner to be described later for cleaning thev air which is delivered to chamber and thence to the compressor unit.

Mounted upon the shaft 26 at the upper endv thereof is the blower fan 28 which is housed in the casing 29 provided with the intake opening 30 and the exhaust opening 30' through which the blower furnishes combustion air to an oil burner as shown in Fig. 3.

The shaft '26 is provided with the reduced portion 32 which it will be observed is eccentric with respect to the shaft 26. Mounted upon portion 32 of the shaft is the compressor pump element 32 which delivers compressed air to the main pump chamber. The reduced portion 32 of the shaft rotates with respect to the pump element 32 causing the pump element 32 Jto have a movement resulting in approach of the element toward thepump walls in such a manner that the point of minimum clearance travels around the inner periphery of the annular pump housing 32a in a counter-clockwise direction as shown by the arrow in Fig. 2 as the shaft 26 rotates in a counter-clockwise direction. .The compressor pump element 32 is provided with a slot '31 with which the pivotal member 31 cooperates to prevent rotation of element 32'. The compressor pump is provided with the inlet 33 and the outlet 34 which is connected to the exhaust lpassage 42 as shown by dotted lines in v Fi'g. 1 which in 'turn is connected to the oil and air separator 43 Vprovided with the oil delivery passage 44 and the air port 45.l j

It will be observed thatthe casing lois provided with the chamber 35 in which the annular shield 25 is mounted. At the left-hand side of this chamber 35 is an inlet opening 36 which has slidably mounted therein a valve 37 provided at one end of its stem with a spring 38, the compression of which can be adjusted by means of thescrew collar 39. The other end of the valve stem cooperates with a metallic bellows member 40. This valveopens and closes the port 36 inresponse to pressure changes within the compression chamber. Leading from this port 36 is the air intake passage 41 shown partly in section in Fig. 1 and which. leads to the air intake passage 33 of the compressor pump as shown in'Fig. 2. The air under pressure is delivered from the separator 43 to the compression- -pump housing as the pump element 32' moves its pointof minimum clearance around the periphery of the pump housingvfrom the position shown in Fig. 2. The air trapped between the element 32' and the annular pump housing 32a as far as the discharge passage 34 is forced through the discharge passage 34 as the point of minimum clearance of element 32 moves in a counter-clockwise direction from the intake port to the discharge port 34. Air at the same time is drawn through the intake port 33 and this second charge of air is in a similar manner forced around the inside of the pump housing as the point of minimum clearance of element 32' moves in a counter-clockwise direction. This operation is repeated so that air is continuously pumped into the compression chamber.

A' second reduced portion 47 of the shaft 26 which portion is offset and carries thereon the oil pump element 48I which is similar in construction and has the same operation as the compressor. pump element 32'. The path of the oil into the compressor unit is through the conduit 49 .which directs oil to the trap51 provided with the filtering screen y52. A valve attached to a metal bellows 50 and having a spring 50 resiliently opposed to the bellows controls the valve opening to the trap 5l. When the pressure in the trap 51 falls b'elow atmospheric due to de mand thereon the metal bellows collapses and opens the valve port to permit more oil to enter the trap. The oil after being filtered by the screen passes into the conduit 53 and into the compressor Icasing which is provided with the in the conduit 56. After being delivered to the r oil sump the air pressure upon the oil surface forces the oil through the filtering screen 59 which is supported by means of the ring member 58 rto which are attached the resilient springs 58 which support the screen ring against the bottom of the bearing 27'.

The oil then passes through the opening 60 in the cap 57 attached by screws 57 to the lower bearing 27' of the motor shaft 26. The oil passes up through the drilled oil feed 61 in the shaft 26 and is discharged through opening 63 into the vapor relief chamber 64. Oil for lubricating the air compressor pump is discharged through the opening 62. From the chamber 64 the oil is discharged to the oil burner nozzle 104 through the passageway 65, and conduit 105. Any air which has been occluded in the oil rises to the top of the vapor relief chamber due to the-reduced pressure in the vapor relief chamber and is forced up between the motor shaft and the bearing 27 from where the air joins the incoming air through the motor. Any oil which seeps through the bearing 27 is thrown by the centrif ugal action of the motor to the shield .24 from which the oil is thrown against the shield 25 and into the chamber 35 of the casing 10. This oil returns to the pump with the incoming air through the air inlet 36.

l Referring to Fig. 3, the blower compressor unit is seen mounted on the top of the oil burner boiler 100. A ring 110 is rigidly supported on top of the boiler 100 by means of the feet 109.

The blower housing 29 is mounted on the ring- 110 and supported thereby. 'Thus it will be noted that all parts shown in Fig. 1 except. the fan housingl 29 and legs 109 are carried by the main casing head 10. This main casing head is resiliently suspended from the ring v11 by means of the suspension members 111. Thus all of the moving elements of the device are carried by the resilient support 111. The main casing 10 with all of the elements which are attached thereto as shown in Fig. 1 including the electric driving motor and all of the air compressor and oil pump elements are resiliently suspended from the ring 110' by means of the suspension members l111. This suspension reduces the noise due to any vibration the compressor unit might have during operation. The unit is enclosed in a casing 107 on top of the boiler and air is admitted to the casing through the louvers 108 and the oil supplied by means of theA conduit 53. The exhaust of the blower is connected by means of the conduits 101 and 102 to the casing 103 surrounding the oil burner nozzle 104. This supplies some of the secondary air necessary for the flame. The remainder of the air passes through the conduit 101 to the lower part of the combustion chamber. Oil leaves the compressor unit by means of the conduit 105 to the nozzle 104 and the air is delivered by means of the conduit 106 to the oil burner nozzle. Y

The operation of my invention is as follows: When the motor `20 is energized the rotor 22 rotates the blower fan 28 which takes in air through the opening30 formed in the top of casing 29 and discharges the greater part of it through the opening 30' to the oil burner apparatus as described above. A small part of the air after passing through the impeller blades of fan 28 is delivered to the intake of the compressor pump passing through the space beneath the blower fan orimpeller 28 and down through the openings 23 in the rotor of the motor cooling the motor as it passes through the openings. A vortex is created in the space beneath the blower fan or impeller 28 by the rotating rotor and fan which prevents large particles of dust from following the air to the rotor. The air is then delivered to Y the enclosed space between the underside of the motor and the top of .the casing head 10 and from this space the air passes between the rotating oil shield 24 and the stationary oil shield 25.

. The comparatively high vvelocity vortex in the space between the top of the motor and the blower fan tends to prevent dust from following air through this space. In the chamber below the stationary shield is the intake 36 of the air compressor. In this chamber any dust'remaining in the air will be trapped in the oil which has enterd this chamber from the vapor relief cham- .ber as described above and passes through the compressor intake 36. The air together with the small amount of oil which has found its way into the chamber 35 then passes through the conduit 41 into the pump intake 33 through the pump and to the exhaust passage 42 to the oil and air separator 43. AThe particles of oil and foreign matter pass downwardly through the conductor 44 into the oil sump and the air free from oil and other foreign particles passes upwardly through the port 45 in the oil separator and thence out through the discharge passage 46. Most satisfactory operation can not be obtained without the separator. Thus the air which is delivered to the oil burner nozzle 'reaches the nozzle free from dust and dirt and any oil or other foreign particles which may have reached the intake of the compressor pump.

Although the compressor pump is continuously operated and although the amount of air delivered to the oil burner nozzle may be varied the pressure within the compression chamber is maintained relatively constant by means of the bellows-operated valve. When the pressure within the chamber rises above a predetermined limit the bellows 40 collapses and the valve 37 is closed against the action of the spring 38 the compression of which can be adjusted for various pressures within the compression chamber. When the pressure within the chamber again reaches a predetermined value the valve again opens permitting air to again enter the chamber and thus lmaintaining the pressure within the tank at a self-priming, that is when the pump is deenergized the pressure within the compression chamber becomes equalized with the pressure outside `of the compression chamber and the valve `closes to maintain an oil seal 4so that oil will not siphon from the storage tank. From the trap the ol passes through the conduits 53, 53', the valve 54, through the conduit 55, through the pump 48, thence to the discargepassage 56 to the check valve 56 which operates to open when the pressure in the discharge passageway builds up, and thence to the oil sump l1. If and when the oil level rises to a predetermined limit the float-operated lever closes valve 54 and thereby prevents the oil pump from pumping any more oil into the oil sump.

The pressure on the surface of the oil within the oil sump forces the oil up through the drilled shaft 26, as heretofore described, for lubricating the motor shaft 26 by means of passage 62 and for delivering the oil through the discharge passage 63 to the vapor relief chamber 64 from which it passes out of the discharge passage 65 to the oil burner nozzle 104 through pipe 105 as shown in Fig. 3. As has been heretofore described occluded air passes up between the shaft andthe upper bearing 27 and is discharged into the chamber 35 from which it passes to the compressor pump 32.

Due to the fact that the oil and air are delivered to a common chamber the pressures are equalized and pulsations due to the interaction of the pressures common in many oil burners-are prevented.

In Fig. 4 is shown a modification of my blower compressor unit. The intake to the oil pump differs from the construction shown in Fig. 1. Oil enters the unit from the trap 51 by means of the passage` and to the intake of the pump by means of conduitv 73 and iindsits way into the sump in the same manner as in Fig. 1. A casing 71 provided with a valve is attached to the conduit 73. It will be seen that as the oil level rise'z above a certain point the float 72 opens the valve in casing 71 so that the conduit 74 opens into the intake conduit 73. When this level is reached by supply until the level of the oil in the. tank :fallsA to a position such that the valve-in the casing lrIl closes.

In this modification the oil for the nozzle does not passup through the shaft 26 as in Fig. v1. A conduit '77 is provided extending to the bottom of the sump tank above the screen 59. The exhaust passage 75 is provided with the valve 76 which may be adjusted by means of the cap member 76 a predetermined degree. i

of passing up through the shaft to the oil burner nozzle passes up` through the conduit '7'7 to the to adjust the rate of ow through the exhaust passage from the sump. A small vapor release lchamber 75 is provided in the exhaust passage 75 above the valve '76 as shown. While the oil is passing through chamber 75( any small air bubbles occluded in the oil rise and separate therefrom. Clearance is provided around the valve stem to the chamber 35 in the casing 10. The clearance in the drawings is exaggerated for the purpose of illustration. This clearance has several functions. A It permits occluded air in the oil being fed to the oil burner nozzle to escape to the chamber 35 along with'any oil that might leak past this clearance in a manner as described in connection with theI apparatus shown in Fig. 1. This oil is sufficient to lubricate the air compressor and is returned to the sump in the same manner as in the case of the structure shown in Fig. 1. Another purpose'of this clearance is to provide a siphon break. Thus if for some reason the valve within the nozzle which may be of any suitable form (not shown) for controlling the oil outlet should fail to close or a break occurs in the line between the exhaust passage 75 of the compressor nit below the level of the oil within the sump tank, unless some means is provided for breaking the Siphon action the oil will siphon into the oil burner cornbustion chamber duringperiods of shutdown. During such shutdown periods the pressure within the sump chamber is quickly equalized with the outside pressure through the air outlet 46 as well asthrough the air inlet valve 37 which immediately opens when the pressure -is reduced. `Thus although the air pressure on the oil is relieved, a siphoning action through the pipe 77 might occur except for the siphon breaking action due to the clearance around the stern of valve 7.6.

The lubrication in this modification of my invention is obtained in the same manner as in the structure shown in Fig. 1 through the shaft 26. 'Ihe chamber 64, however is not connected with the exhaust passage of the burner. The sole pur--` pose ofthis chamber is to provide an oil seal for the tank t9 prevent leakage of air therefrom and tlius maintain the pressure within the tank. Any oil which finds its way past the bearing 2'?V is returned to the oil sump in a manner similar to the action of the structure shown in Fig. 1.

It will be noted that the trap 51 is provided with a valve 51' for closing the exhaust from the trap. This valve performs the function of preventing siphoning back from the sump of the compressor unit should a break occur in the trap 51 or the supply line 49 between theoil supply and the trap. The operation of the modification shown inFig,

4,15' very similar to that of Fig. 1. The .only dirference is that the oil is by-passed through the pump when the level within the sump tank exceeds Further, the oil insteadexhaust passage 15. the amountl of oil passing automatic lubrication.

means of the valve 76.

It will thus be seen that I have provided a vcompact blower compressor unit which is easily balanced' and which is provided with permanent my device a unique method of providing air free from`dust and oil and oil free from air and which willinsure proper combustion at the oil burner nozzle. I havealso provided automatic means for maintaining the pressure within the compression chamber even and constant and for insuring Ik.a constant oil level within the oil sump. My

' invention lis susceptible of being modied to meet the different conditions encountered in its use, and I therefore aim to cover by the appended claims all of the modificationswithin the true spirit and scope of my invention. A

What I claim as new and desire to secure by Letters Patent of the United States, is:

through the oil burner nozzle'being regulated by I have also provided inl having operating partsmounted on and driven by said shaft for pumping air and oil under press'ure into Asaid tank, one end of said shaft extending below the level of the oil in said tank and having passages therein for supplying oil to said'pumping means and said bearings for lubricating the same, the pressure in said cham.- ber forcing oil through said passages.

2. An oil burner compressor unit including a pressure equalizing tank, a motor vertically mounted on the top of said tank and having a shaft extending within said tank through the top thereof, -a pressure sealingchamber in the top of said tank through which said shaft extends,

oil and air-pumps having operating parts operatively connected to said motor by said shaft for pumping oil and air under pressure into said tank, thc end of said shaft within said tankY extending below the level of the oil in said tank and having passages extending therethrough from said oil to said chamber, the pressure in said .tank forcing oil through said passages in said shaft to said chamber for providing an oil seal for said pressure tank around said shaft.

3. An oil burner compressonunit having a,

chamber in the topl of said `tank through which said shaft extends and said chamber being'connected with another of said-passages in said shaft, the pressure -in said tank forcing oil through said passages in said shaft to said compressor for lubricating the same and to said chamber for providing an oil seal for said pressure tank around said shaft.

4. An oil burner compressor unit having a pressure equalizing tank, a motor vertically mounted on the top of said tank and having a shaft extending within said'tank through the top thereof, a bearing for said shaft adjacent said motor, an air compressor and an oil pump connected to be driven by said shaft for pumping air and oil into said tank under pressure, outlet means in said tank for the oil and air, said oil outlet means extending adjacent to said shaft, a bearing for the end of said shaft supported within said tank, said shaft extending below the level of the oil in said tank, passages in said shaftfor lubricating said bearings and said compressor and for feeding oil to said outlet means, the pressure in said tank forcing oil through said passages,

5. An oil burner compressor unit including -a tankv having an upper part and a lower part and providing a pressure equalizing chamber, a

motor having a shaft extending vertically within said chamber Kthrough the top of said tank, a compressor and oil pump in said chamber havingv inlet means extending through a Vwall of said tank, said compressor and pump having movable parts connected to said shaft for pumping oil and air into said chamber under pressure, outlet means in said tank from'l said chamber for the oil and air, said oil outlet means extending to said shaft, said shaft extending below the level of the' oil yin said chamber, passages in said shaft for feeding oil to said outlet means, a screen associated with the lower end of said shaft for straining the oilpassing up through the passages. in said shaft, the lower part of said tankl maintaining said screen in position, the pressure in said tank 4forcing oil through said screenf -and passages, and a clamp for holding said upper` and lower parts of said tank together to form an air-tight fit. g 6. An apparatus for supplying oil and air unde pressure to anoil burner including an equalizing pressure tank, a motor vertically mounted on top of said-tank and lhaving a shaft extending through the top thereof, said shaft having a Iplurality of offset portions of successively smaller diameters extending within said chamber, an

air compressor having a rotor mounted on one of ,said offset portions, an oil pump having a rotor mounted on another of said offset portions,

said compressor and oil pump pumping air and oil under pressure into said tank, said shaft having an end portion within' said tank of smaller diameter than said offset portions and whereby said shaft may be extended within or withdrawn from saidtank through the top thereof in Iassembling or disassembling said compressor unit.

7. An oil burner Vunit including a casing providing a pressure chamber for oil and air, a motor mounted on said casingfand having a shaftextending'through afwall of said casingv into said chamber, oil and air pumping means within said chamber operatively connected to saidshaft for pumping oiland air under pressure intol said chamber, a bearing for said shaft in said` wall,l

an oil sealed chamber around said shaft to prel0 vent leakage ofair from said pressure chamber `through the bearing, and meansv connected with said pumping means for returning the oil passing through said bearing to said chamber.-

9. An oil burner unit including a casing prol5 viding a pressure chamber for air and oil, a motor having axially disposed air passages therein and vertically mounted on the top wall of said casing and having a driving shaft extending from the top and bottom thereof with the bottom end ex- 20 a tending into said chamber, air and oil pumping means mounted within said chamber and connected to be driven by said shaft for pumping oil and, air under pressure into said chamber, and

a blower mountedvabove said motor and having 25 an impeller rotatably supported on the top end of said shaft and having a housing with an air inlet r. opening formed thereinabove said impeller and cooperating' with said air passages of themotor to supply clean air from the vortex beneath said 30 impeller 'downwardly through the motor to said pumping means. Y l

10. An, oil burner unit including a casing providing a pressure chamber for -air and oil and having separate air and oil inlets and outlets 35 therein, -an electric motor having air passages therein and mounted on said'casing over the said 'air inlet therein and .provided .with a shaft extending on opposite sides of the motor with one end of said shaft extending inside said chamber, 4

air and oil pumping means'mounted inside said casingl in operative relation with said shaft and communicating with said air and oil inlets for pumping oil and air under pressure into said chamber, and a blower having an impeller drum closed at one side and rotatably supported on the other end of said shaft and having 'a housing with an air inlet opening formed therein at the Vopen side of said impeller drum" and cooperating with said air passages of the motor to supply clean air from the vortex inside said housing adjacent the center of the closed side of said impeller drum through the motor to'` said air inlet in said casing.

11. An oil burner unit including a casing providing a pressure chamber for air and oil, and having separate air and oilfinlets and outlets in said casing. a motor having axially alignedair passages formed therein and verticallyvmounted on the top wall of said casing and having a driving shaft extending from the top and bottom thereof with the bottom end extending into said chamber, air and oil pumping means mounted` within said chamber and connected to be driven by said shaft and communicating with said oil and air inlets for pumping-oil and air under preso5 ing an impeller rotatably supported on the top 70 end of said shaft and having a housing with an inlet opening formed therein above said impeller and cooperating with said air passages of the motor to supply cleanA air from the vortex be- ,neath said'impeller downwardly through the 75 'l' 1,2."An oil burner unit including motor `driven 5 oiland air pumping 4means for supplying oiland air under'pressureto abur-ner and a centrifugal blower operatively associated with said-pumping means and having an air inletat one side thereof and separate air outlets, one communicating between the 4vortex lat Vthe other side of the blower kand saidair pumping means to supply clean` air thereto 'and the' other communicating VWith the periphery of the blower to supply the residue of uncleaned air to the burner.

13. An oil burner` air and oil supply unit including motor driven oil and air pumping means for supplying oil and air under pressure to a burner, and a blower operatively associated with said pumping means and having a centrifugal impeller drum closed at one side and a housing provided with a central axial air inlet at the open side of said impeller drum and a main radial air outlet therefrom for supplying air to the burner and provided with an auxiliary central axial air outlet from the vortex at the said closed side of the impeller drum communicating with said air pumping means to supply cleaned air thereto.

14. An oil burner air and oil supply unit includ--y ing a casing providing a pressurevchamber for supplying oil and air under pressure to a burner, Aa motor driven oil and air pumping means mounted upon and connected to the casing for pumping oil and air under pressure into said chamber, and a centrifugal blower operatively associated with said pumping'means and having an lair inlet at one side thereof and separate air outlets, one communicating between the vortex at the other side of the blower and said air pumping means to supply clean air thereto and the other communicating with the periphery of the blower to supply the residue of uncleaned air to the burner.

15. An oil burner air and oil supply unit in' cluding a casing providing a pressure chamber for supplying oil and air under pressure to a burner, motor driven oil and air pumping means mountf ed upon and connected to said casing for pumping oil and air under pressure into said chamber, and

a blower operatively associated with said pump- 16. An oil burner unit comprisinga casing head 'provided withL an air inlet passage extending therethrough, oil and air pumping means mounted on one side of said casing head with the air pumping means in communication with said air inlet passage, a driving motor for said pumping means mounted on the other side of said' casing to form an air chamber between the motorand the casing communicating with said air passage. a blower having an impeller mounted on the rotor element of the motor and a housing cooperating with the motor frame to admit airr to one side of said impeller and conduct air from the vortex adjacent the other side of said impeller through the motor frame vto said air chamber, and acasing surrounding said oil and air pumping means and connected t0 the casing head to form a closed` electric driving motorhaving a rotor provided v lwith a 'shaft journalled in said bearings anda frame provided with means for mounting the frameon said top head concentricallyV around the rotor to form an air chamber communicating with said air pumping means, a blower having a rotor mounted on the upper end of the motor shaft and a housing cooperating with the motor frame to admit air to one side of the rotor and conduct air from the vortex at the other side thereof to said air chamber, and a tank telescoping over said pump housing and connected to the top head thereof to form a sump chamber for receiving the oil and air from said pumping means.

18. An oil burner air and oil supply unit in,- cluding air and oil pumping means having an annularhousing provided with heads at the top and bottom thereof each provided with a bearing and having the top head extending beyond the periphery of the housing, an electric driving motor having a rotor provided with a shaft journalled in said bearings \in operative relation with said pumping means and a frame mounted on the top head to form an air chamber between the motor and the head with air supply passages extending through the motor to said chamber and close the rotor and conduct air from the vortex beneath said rotor to said air chamber, and a tank -telescoping over said annular pump housing and connected to the top head thereof to forma sealed sump chamber surrounding said pump -housing for receiving the oil and air from said pumping means and qualizing the pressure thereof.

19. An apparatus for supplying air and oil under pressure to an oil burner including a separable two-part tank having separate inlets and outlets for both oil .and air provided inv one part thereof with the oil outlet terminating adjacent the bottom of the tank and the air outlet terminating adjacent the top of the tank, air and oil pumping means mounted within the tank on said one part and connected with the air and oil inlets to discharge air and oil under pressure inside the tank, an electric driving motor mounted outside the tank on said one part and operatively connected with said pumping means, the equalized air and oil pressures within said tank acting to force the oil and air in said tank to said 20. An' apparatus for supplying air and oil under pressure to an oil burner including a separable two-part tank having separate inlets and outlets for both oil and air in one part thereof with the oil outlet terminating adjacent the bottom of the 'tank and the air outlet terminating adjacent the 'electric driving motor mounted outside the tank on said one part and operatively connected with said pumping means, an oil strainer mounted within said tank adjacent and in operative relation with said oil outlet, and clamping means for holding the parts of the tank together under pressure and for permitting the parts to be separated to clean said strainer.

21. An apparatus for supplying oil and air under pressure to an oil burner including a two-part tank having the bottom part thereof separable from the top part and having separate inlets and outlets for both oil and air in the top part thereof With the oil outlet terminating adjacent the bottom of the tank and the air outlet terminating adjacent the top of the tank, air and oil pumping means mounted within the tank on said top part thereof and connected with the air and oil inlets to discharge air and oil under pressure inside the tank, an electric driving motor mounted outside the tank on said top part thereof and operatively connected with said pumping means, an oil strainer mounted within the tank on said pumping means and disposed adjacent and in operative.

formed therein, a driving motor mounted on one side of the casing head with the motor shaft extending through the head, oil and air pumping means mounted on the other side of said casing head in operative relation with said shaft and having the inlets thereof communicating with said air and oil inlet passages, and a casing telescoping over said oil and air pumping means and connected to the casing head to form a closed sump chamber for receiving oil and air from said pumping means and equalizing the pressure thereof before discharge through said outlet pas-` sages.

23. An oil burner unit including a casing head provided with air and oil inlet and outlet passages terminating adjacent the edges thereof, an electric driving motor mounted on one face of the casing head with the motor shaft extending there- A through, a bearing in the head for said shaft, oil

and air pumping means mounted on the other face of said casing head in operative relation with said shaft and having a housing provided with oil and air inlets communicating with the said inlet passages formed in the casing head, and a tank telescoping over the housing of said oil and air pumping means and joined to said casing head to form a sealed sump chamber for receiving oil and air from said pumping means and equalizing the pressure thereof before discharge through said outlet passages.

24. An oil burner unit including an electric driving Vmotor having separate frame and rotor elements, a casing head provided withmeans for mounting the motorv frame and rotor elements in operative relation on one side thereof including a bearing for the rotor shaft'and supporting means for maintaining the frame concentric therewith, said casing head having inlet and outlet passages for air and oil formed therein, oil and air pumping means mounted on the other side of said casing head in operative relation with said rotor of the motor and having inlets communicating with the said inlet passages formed in the casing head, said oil and air pumping means being provided with a bearing cooperating with said bearing in the vcasing head for rotatably supporting the rotor shaft of the motor, and a casing telescoping over said oil and air pumping means and connected to the casing head to form a closed chamber for receiving the oil and air from said pumping means and equalizing the pressures thereof before discharge to said outlet passages.

25. An oil burner unit including a casing head provided with a shaft bearing extending vertically through the center thereof and provided with oil and air vinlet and outlet passages formed therein, a driving motor vertically mounted on top of said casing head with the motor shaft extending through said bearing, pumping means for oil and air mounted on the bottom of said casing head in operative relation with said shaft and having a second bearing for the motor shaft and provided with inlets communicating with the said inlet passages, and a casing telescoping over said pumping means and detachably connected to the casing, head to forml .a sealed sump chamber for the. oil and air discharged from said pumping means with the said air outlet passage communicating with 'the air at the top of said sump chamber, said pumping means having a passage provided therein for connecting the said oil outlet passage with the oil at the bottom of said sump chamber.

26. An oil burner unit including a circular casing head provided with a shaft bearing extending through the center thereof and provided on one face thereof with a mounting flange concentric With said bearing, an electric motor having a frame adapted to be mounted on said flange and a rotor provided with a shaft adapted to be journaled in said bearing and extend through the casing head, oil and air pumping means having a stationary housing connected to the other side of said casing head and movable parts operatively connected to said shaft and provided With f ing means before discharge thereof through said outlet passages. g

27. An oil burner unit including a casing head provided with a bearing extending vertically through the center thereof and having separate inlet and outlet passages for air and oil formed therein, a driving motor mounted on top of the casing head with the motor shaft extending through said bearing and provided with means for supplying air through themotor ,to said air inlet passage, oil and air pumping means mounted on the bottom of said casing head in operative relation with said shaft and having air and oil inlets communicating with the said inlet passages .in the casing head, and a tank telescoping over said oil,and air pumping means and having its upper edge sealed to the casing head to form a closed sump chamber for temporarily receiving oil and air from said pumping means before discharge thereof through said outlet passages. y

28. An oil burner unit including air and oil vpumping means having an annular pump houseating with the interirof said chamber, and an electric driving motor havinga rotor provided witha shaft'mounted in said bearings and a frame mounted on said one head invoperative relation with the rotor.

29. An -oil burner unit including oil and air pumping means having an annular pump housing provided withv a head at one end thereof extending beyond the periphery of the pump housing and having. air and oil inlet and outlet passages formed therein, a pump driving motor mounted on said head, and a casing telescoping over said pump housing and connected to said head to forma closed sump chamber for receiving oil and air from said pump housing before discharge thereof through said outlet passages.

30. An oil` burner unit including. air and oil pumping means having anannularfpump housing provided with a head at .one end thereof extending beyond the periphery of the housing, an 4electric driving motor for said pumping means ,mounted on said head to form an air chamber between the motor and the head, said-motor having passages ,formed therein for supplying air to said chamber and said head having a passage extending therethrough f or supplying air from the air chamber to the air pumping means in said pump housing said head having an oil inlet passage communicating with said oil pumping means and a tank elescoping over said pump housing and connected to said head to form a sump chamber for receiving oil and air, said pumping means delivering oil and air to said sump chamber.

i WALTER O. LUM. 

